Windows ha un nuovo pericoloso bug: come difendersi

Si chiama PrintNightmare, riguarda tutti i sistemi operativi di Microsoft e permette agli hacker di attaccare i computer connessi in rete: ecco come difendersi.


Giuseppe Croce Giornalista

Peppe Croce, giornalista dal 2008, si occupa di device elettronici e nuove tecnologie applicate al mondo automotive. È entrato in Libero Tecnologia nel 2018.

Torna l’incubo delle stampanti su Microsoft Windows: dopo il bug classificato come CVE-2021-1675 e parzialmente risolto a inizio giugno 2021, ora è stato scoperto il nuovo bug CVE-2021-34527 che è molto simile ed è stato ribattezzato “PrintNightmare“. Once again it's a dangerous security bug, which allows hackers to execute dangerous code on Windows PCs.

Unfortunately, at least at the moment, not even Microsoft has figured out how dangerous PrintNightmare really is so much so that it hasn't yet assigned it a severity rating (which is usually done to indicate which bugs are potentially more dangerous). Microsoft, however, claims to be aware of the bug and to be working to find a solution. In the meantime, it urges everyone to update their operating system (all versions of Windows are affected by the bug, not just Windows 10) with the security patches released in early June to fix the previous bug CVE-2021-34527 and to follow some preventive measures that can mitigate the risk of attack by a hacker.

How PrintNightmare works

The PrintNightmare bug stems from an error in the code of the so-called Print Spoiler in Windows, which is the part of the operating system responsible for sorting all calls to the printer and routing documents to this device.

The problem mainly affects servers and corporate networks, but in theory any computer connected to a network that has been attacked by exploiting the bug could in turn be attacked.

It could and, perhaps, already has been because according to Microsoft itself, the PrintNightmare bug has already been exploited at least once.

How to defend against PrintNightmare

PrintNightmare doesn't have a security patch yet, so there's no update dedicated to it that closes the flaw once and for all. Microsoft, however, is urging system administrators and ordinary users of all versions of Windows to update their operating systems.

On June 8, Microsoft released an update to fix the previous print spoiler bug, and according to the Redmond-based company, this upgrade is among the useful mitigation measures to limit the risks posed by the new PrintNightmare.

Another useful measure is to disable the print spoiler, which is the gateway for possible hackers to enter. The problem is that disabling the spoiler will cause the printer to stop working. Alternatively, you can disable remote printing, which is the service that allows you to print (within a company network) a file sent from another computer. This maneuver, however, belongs to the network administrators and not to the single user.